People who are unable to eat or swallow regular food are provided with enteral feeding. The typical apparatus for enteral feeding comprises a single lumen tube structure, called a feeding tube, the distal end of which has aperatures for delivery of the enteral feeding solution to the stomach or small intestine. Some feeding tubes are threaded through the nasopharynx into the patient""s stomach or small intestine. Others are placed through a stoma in the abdominal wall. The proximal end of the feeding tube is connected to a container of enteral feeding solution by a tubing set which is formed integrally with, or securely fastened to, the container. The feeding solution may be supplied in prefilled bags, or standing reservoir containers that may be filled on-site. It requires special training to place a feeding tube in a patient. Once the tube is properly in place, effort is taken to not dislodge it. Similarly, the feeding tube is not withdrawn or replaced until it is necessary to do so. Also, once the tube is in place, medications cannot be administered through the mouth.
Adding the medications to the feeding solution in the 250 ml. or more standing reservoir container of feeding solution, however, is not the answer. Adding medications to the feeding solution unnecessarily increases the time of administration of the medication. In addition, unless the medication is very thoroughly mixed with feeding solution, approximating the dosage of medications administered from the combined volumes of feeding solution and oral medications given is not only difficult to calculate, but also difficult to measure accurately, as the volume of medication is so much smaller than the volume of feeding solution. If the container of feeding solution is a tamper-proof container, it may be impossible to mix the oral medications with feeding solution. Indeed, the enteral feeding solution may be supplied in a tamper-proof container or bag, to provide a fixed, known, quantity and composition, as well as to prevent its alteration or contamination.
One can attempt to get the medication into the open end of the indwelling feeding tube, such as with a syringe, but a good connection and accurate administration is not possible. The open end of the typical indwelling feeding tube has a port shaped like the inside of a cone. It is made to accommodate the nozzle tip of the tubing set of a standing reservoir. The port is made of flexible, rubbery plastic material, and the tip of an e.g. irrigation syringe can be forced into the port to get some purchase. This is not leak proof, however. Newer feeding tubes have a Y-port, said to be for irrigation and administration of medications. However, the addition of another similarly shaped port does not provide a means for making a more secure attachment to the port, to prevent leaks or stabilize the apparatus.
Home-bound patients on enteral feeding solutions(with a feeding tube still in place) are instructed to hold the tip of a 60 ml syringe barrel in the port, and pour feeding solution into the syringe barrel. This delivery arrangement is barely adequate for the patient who must attend the feeding, and inappropriate for nursing staff. In addition, it lacks the leak-proof seal, clamp and drip chamber generally used to oversee the correct administration of medications.
Examples of tubing sets for enteral feeding using a feeding pump are the Ross Medical Nutritional Products Pump and Gravity Set with Piercing Pin, and the Ross Nutritional Enteral Pump Set with Piercing Pin for use with a non-Ross Pump. Both tubing sets comprise a piercing pin to connect to a pin port provided on a feeding solution bag or reservoir. The piercing pin is connected to a tubing path with a drip chamber and roller clamp disposed along the path of the tubing, and having a nozzle shaped connector at its distal end, for attachment to the port indwelling feeding tube. Other tubing sets are made with a threaded aperture in place of the pin. The feeding solution container used with this tubing set has a threaded opening. Though a wide variety of tubing sets are commercially available, none are provided with means for attaching to a dosage vessel, such as a syringe, needed to accurately administer medications to the indwelling feeding tube. In addition, commercially available enteral feeding containers are not good dosage vessels. Their large reservoir size makes them inappropriate for administration of small volumes of medications, as the medications coat the inner wall of the container, leaving a portion of the dose unadministered.
Medications are not typically packaged in small volume containers that can be accessed with a tubing set. Without the proper connectors, the attachment to the feeding tube will be unstable, and the nurse required to hold the connection to stabilize it. An accidental destabilization or disconnnect will create a leak, leaving the nurse with the knowledge that some medication was given but not knowing how much. It may not be possible to correct for the mis-administration. Even with considerable effort, the unstable connection may make it impossible to complete the administration of the dose. Placing another tube in the patient is not the solution.
U.S. Pat. No. 5,527,280 illustrates a gastric or stomach feeding tube for placement through an abdominal stoma into the stomach, and a narrow jejunal feeding tube which passes through the gastric tube. The gastric feeding tube is fixed in position with the distal end held within the stomach by balloon. Gastric feeding is administered through the internal bore of the gastric tube. A narrow jejunal feeding tube may be threaded through the gastric feeding tube to the small intestine. This device is designed to permit a transition from gastric to jejunal feeding without having to insert a jejunal tube alongside the gastric tube. The trade-off is in the larger overall diameter of the stoma for inserting this large bore device, but this is considered superior to creating the irregularly shaped stomal opening needed for side-by-side tubes.
The device is also described as a feeding and medicating device, the gastric tube being available for administering medications after the jejunal tube is extended for feeding. After switching from gastric to jejunal feeding, the lumens are in position to introduce medications through the gastric tube openings. Jejunal feeding rates, however, are so much slower than stomach feeding rates that the switch would not be made simply for alternate delivery routes for oral medication. In addition, the ports for the gastric and jejunal tubes are constructed for attachment to the enteral feeding tubing set, and have no means for connecting a small dosage vessel. Thus, though a variety of lumens are offered by the device, none provide adequate means for intermittently administering medications through the feeding tube.
U.S. Pat. No. 5,071,405 illustrates a single lumen multi-port abdominal stomal feeding tube. The feeding tube has three ports. One is the main inlet port for enteral feeding solution. Another, is the Y-port, for the administration of medications, and for gastric suction, if needed. The last port is provided to inflate/deflate a balloon which abuts the skin about the stoma, anchoring the device against the skin. The Y-port, has a plug for use when the lumen is not in use. In terms of structure, this device is similar to simply adding a Y-port at the open end of the indwelling feeding tube. While the Y-port appears to offer a method for delivering medications while feeding, in use, it is very time consuming and difficult to administer medications through the Y-port. As with adding medication to a container of enteral feeding solution, administration time is slowed by being combined with the feeding solution in the tube. In addition, difficulties in feeding may affect the quantity and timing of the administration of medications. In addition multiple ports provide multiple access points for possible contamination, requiring repeated cleaning. Providing multiple ports provides no teaching or suggestion of what is needed to attach to the port, namely a dosage vessel with a secure fluid path, which can be firmly and reliably attached to the port of a feeding tube, to accurately deliver a dose of medication. Thus the need still remains for a stable, secure connection for administering medications to a patient through an indwelling enteral feeding tube.
Use of the apparatus of the present invention provides a number of advantages. When a nurse has to administer a number of medications, the liquid medications are poured into and accumulated in the dosage vessel, and administered into the open port of an indwelling feeding tube. In addition, the nurse may either cap the vessel, or mount the apparatus, or both, quickly eliminating the danger of unsecured or mis-administered medications. The apparatus of the present invention permits the nurse to make a secure attachment to the open port of the feeding tube, and remove both hands from the attachment. If filling the dosage vessel at the bedside, the nurse has both hands free to place medications and/or food into the dosage vessel, and correctly and accurately administer the necessary medications and/or food. In addition, she may attach the apparatus, and then have both hands free to open a can of feeding solution.
The present invention provides an apparatus for the accurate feeding of medications, to the indwelling feeding tube of a patient on enteral feeding. The apparatus has a small dosage vessel connected to a secure fluid path, which makes a fluid-tight connection to the open end of an indwelling feeding tube. The dosage vessel may have a top opening for adding medications to the vessel. After adding the medication, a fluid tight cap may be placed over the top opening, if desired. In another preferred embodiment the vessel may be sealed to form a sealed chamber containing a pre-measured dose. The dosage vessel or sealed chamber may have a volume of from about 25 milliliters to 250 milliliters, and preferably from about 50 to about 100 milliliters. Preferably the vessel or chamber bears lines of volume gradation, so that the nurse may monitor the volume of medications administered from the vessel or chamber. It is also preferred that the cap have means such as a hanging ring with which to mount the apparatus to a stable mounting.
At the distal end of the fluid path is a feeding tube connector for making a stable attachment to the indwelling feeding tube. Intermediate the vessel and the connector, the tubing passes through 1) means for regulating the fluid flow, such as a roller clamp, which may be adjusted to stop, establish or restrict the fluid flow through the tubing, and 2) a drip chamber, or other means to display the rate of flow, may be located intermediate the roller clamp and the dosage vessel. The means for regulating the flow must include means to stop the flow to fill the vessel, or stop the administration of the medication, means to re-establish flow, and means to restrict flow for observation of the flow rate in the drip chamber. The apparatus of the present invention permits a nurse to easily and safely provide medications to a patient with an indwelling enteral feeding tube. In a preferred embodiment, the dosage vessel is similar to a syringe barrel, and it is formed integrally, or securely attached, with a drip chamber. The present invention also comprises a method for administering medications, and bolus feedings using the apparatus of the present invention.